Studies on the Reactivity of a Labile Tungsten Acetonitrile Complex

考察了高活性配合物顺式- cp ^*W(CO)_2(L)Me （1， L=McCN; 2， L=py）对异氰酸酯、噻吩、氢硅烷和氢硅基配合物的反应活性。(1)乙腈配合物1与异氰化物反应生成乙腈取代产物和CO插入产物，其比例随反应温度和异氰化物浓度的不同而有较大变化。在60℃时，插入产物也能很容易地形成，这证明了它作为烷基羰基钨配合物的插入反应具有异常高的反应活性。(2) 1与噻吩的反应导致α-C-H键的高度选择性活化，得到2-噻吩基配合物。(3)吡啶配合物2与伯硅烷和仲硅烷通过Si-H键活化和1,2 - h迁移反应生成碱稳定的氢（硅烷）配合物，硅烯配合物与氢硅烷的反应性研究揭示了其新的反应性，可产生硅烯交换产物和碱稳定的硅基（硅烯）配合物。(4) 1与水合（氢硅基）铼配合物反应生成水合-硅基桥接Re-W杂双金属配合物，其光解作用导致分子内C-H键活化，形成新型的硅基桥接杂双金属配合物。制备了2的钼类似物，并与氢硅烷反应得到碱稳定的氢（硅炔）钼配合物。硅烯配合物与伯硅烷的反应得到硅烷的再分配产物以及碱稳定的硅基（硅烯）配合物。

The reactivities of highly reactive complexes cis-Cp^*W(CO)_2(L)Me (1, L=McCN ; 2, L=py) towards a variety of reagents such as isocyanides, thiophenes, hydrosilanes, and hydrido (hydrosilyl) complexes were examined.(1) Acetonitrile complex 1 reacted with isocyanide to give acetonitrile-substitution and CO insertion products, whose ratio varied substantially depending upon the reaction temperature and isocyanide concentration. Its unusually high reactivity to the insertion reaction as an alkyl carbonyl tungsten complex was demonstrated by the facile formation of the insertion product even at-60℃. (2) The reaction of 1 with thiophene resulted in the highly selective α-C-H bond activation to give a 2-thienyl complex. (3) Pyridine complex 2 reacted with primary and secondary silanes to produce base-stabilized hydrido (silylene) complexes via Si-H bond activation and 1, 2-H migration, and the reactivity studies of the silylene complexes with hydrosilanes revealed their novel reactivity to afford silylene exchange products and base-stabilized silyl (silylene) complexes. (4) The reaction of 1 with a hydrido (hydrosilyl) rhenium complex gave a hydrido- and silylene-bridged Re-W heterobimetallic complex, and its photolysis led to intramolecular C-H bond activation to form a novel silenyl-bridged heterobimetallic complex.A molybdenum analogue of 2 was also prepared and subjected to reaction with hydrosilanes to afford base-stabilized hydrido (silylene)molybdenum complexes. The reaction of the silylene complex with a primary silane gave redistribution products of the silane in addition to a base-stabilized silyl (silylene) complex.